The present disclosure relates to rechargeable lithium-ion containing electrochemical cells and batteries and to a manufacturing method thereof. In particular, the present disclosure relates to a use of an electrolyte in vacuum filling a large format electrochemical cell and to a method for filling the electrolyte into the electrochemical cell used in rechargeable lithium-ion containing batteries.
Lithium-ion containing rechargeable batteries, also called lithium ion secondary batteries or lithium ion batteries, are advantageous because of their large capacities, their extended life times, the absence of a memory effect and have been widely used for small sized applications. Lithium containing rechargeable batteries are widely used for many applications, and have shown to be particularly useful in mobile phones, mobile computers and other electronic devices.
The use of the lithium-ion containing rechargeable batteries, however, is today limited to smaller cells with limited capacities. Just few large scale lithium cell batteries have been presented on the market so far, although there is an increasing need for large scale and high capacity lithium batteries, for example for the use in electric vehicles or as energy buffers or storages in green energy power plants, such as solar farms or wind farms. Storage of large amounts of electricity is becoming an increasing need for future energy solutions.
However, manufacturing of large format lithium containing batteries has not been possible in a manner that allows cost effective mass production of the large format lithium cells. Present production processes are very time consuming mainly due to the time consuming filling of the electrolyte into the cell and do not allow a cost-effective production of large format lithium containing electrochemical cells or batteries.
WO 02/091497 describes non-ionic surfactants as additives to the electrolyte in lithium ion batteries. These additives are mainly used for improving impedance properties of the battery. The document does not relate to accelerating the filling of electrolyte into an electrochemical cell.
WO 2010/004012 relates to ion-mobility in ionic-liquid electrolytes. This document suggests the use alkyl sulphates as anionic surfactants in the ionic electrolyte liquids to improve cation mobility.
US 2007/0287062 A1 discloses a separator for an electrochemical element. The preparation of electric double layer capacitors is also disclosed. This preparation includes manufacturing electrodes, interposing separators between the positive and the negative electrodes and preparing spiral shaped elements. The spiral shaped elements are then placed into cases made of aluminium. The cases without electrolyte are subjected to vacuum treatment. After cooling to room temperature, the electrolyte is only then injected into an electrolyte injection port of the case. Thus, this document does not disclose filling an electrolyte under vacuum conditions and advantages thereof.
It is an object of the present invention to improve the manufacturing of electrochemical cells.